Method of making wrought iron



Dec. 13, 1932. JfAsToN ET AL METHOD OF MAKING WROUGHT IRON Filed July 19, 1928 R O T N E v m al -H.

Patented Dec. 13, 1932I UNITED STATES PATENT orf-ICE- JAMES ASTON AND ADDISON H. BEALE,- OF PITTSBURGH, PENNSYLVANIA, ASSIGNOBS, BY MESNE ASSIGNMENTS, TO A. M. BYERS COMPANY, OF- PITTSBURGH, Imm VANIA, A CORPORATION OF PENNSYLVANIA p METHOD Ol' MAKING- WROUGHT IRON A Application iiled July 19, 1928. Serial No. 294,048.

Our invention relates to the Aston process of making wrought iron, such, for example, as set forth in several United States patents of James Aston, such as No. 1,370,507, grantved- March 8, 1920, for method of making wrought iron pipe; No. 1,412,823, granted April 18, 1922, for method of making wrought iron; and No. 1,469,373 granted October 2, 1923, for manufacture of wrought iron. .f

An object of the invention is to provide for theeformation by the Aston process of a wrought iron sponge or ball having a shape adapting it for particular purposes .and insuring 'substantially complete granulation of the fmetal, even toward the end of the pour. For thesev purposes a ball having at least one horizontal dimension greater than its vertical dimension is formed.

A further object of the invention is to im.

prove the etliciency and economy of the Aston process by refusing of the molten slag employed in the shottlng or granulating operations. As previously carried out, in operating the Aston process of ,making wrought iron, a large mold was partially filled with molten slag'of the desired puddling characteristics, the liquid product of the steel-making process was poured into it to cause granulation of the steel due to the temperature dif-I ference between the steel and the slag bath,

and the puddled iron ball was collected in the lbottom of themold. The excess slag was then poured oii' and the puddle ball dumped out. In such method of operation the excess slag solidified and its heat was wasted.

We have found that we can increase the economy and eiliciency of the process by re using the molten slag va plurality of times, thus avoiding much of the expense of remelting. In carrying out ,our improved method, we prefer to employ a large cup or pot of ferrous material which is ofsuch dimensions and so designed thatit can be and is lined with frebrick or other refractory material. The lined receptacle which we prefer to employ is about 3 feet by 4 feet in interior cross-sectional dimensions, and about 4% to 5 feet deep. A larger receptacle may be used if a larger puddle ball is desired.

Aferred `depth of slag is about 3 feet.

lcast with an upper inwardly proJecting lip or ange 4, if it is tobe lined with llrebrick, such as shown at 5.

In the form shown, the sides diverge upwardly, two of the sides diverging more sharply than the other two sides. The bottom dimensions of the lined vessel are about four-feet along the longer axis by about three feet along the shorter axis.

Suiiicient slag is poured into this rece tacle to lill it to about one-half or two-thir s full. The receptacle should contain suicient slag so that its temperature will bel conserved to the degree desired in the process,

and so that theexcess slag can be re-used.

while in the liquid or molten state. The ret is important-to provide a sufficient depth of slag bath, in order to giye the granules a proper distance of travel so that they have sutcient time to release their contained oxides andv gases into the slag bath before contacting withthe wrought iron ball or mass at the bottom and welding and building up the wrought iron sponge. This desirable time element is obtained by the proper depth of bath. After the pouring in ofthe steel is completed, the gases which cause more or less foaming orboiling, pass oi and the level of the bath usually lowers while the last granules are descending and welding with the spongy mass at the bottom.

They vessel is of such size in at least one horizontal dimension that a ball of desirable y weight may be formed having at least one horizontal dimension greater than 'its `verti cal dimension. Such a ball is particularly well adapted for formation in a hydraulic press into -a bloom of suitable size and shape for rolling into slabs or billets, and by reason of the shape of the ball a suicient depth of Cil slag is maintained over it, even toward the end of the pour, to insure substantially complete granulation of the metal in the overlyin slag.

uring the pouring operation, the temperature of the slag is somewhat increased by reason of the relatively high temperature ofl i the steel entering it.

For proper operation, the slag must be kept sufficiently cool to properly solidify and granulate the steel, several hundred degrees difference being requisite for this purpose. lining the vessel with refractory material the slag remaining above the ball is maintained sufficiently hot so that it can be pouredout into another cup or receptacle. After the shotting operation, the surplus slag is poured into the next cup or receptacle and the puddle ball is then dumped out and goes to the press.

In the second cup or receptacle the same operations may becarried out. After the puddle ball is formed therein the slag may e again poured out into athird cup or receptacle and the slag times.

The advantages of our invention result from the formation of a ball having at least one horizontal dimension greater than its thus re-useda number of vertical dimension, which is particularly suited for pressing into a bloom of desired size and shape and insures substantially complete granulation of the metal, even toward the end of the pour, from the re-use of the while in molten condition, thus conserving its heat, and further from the use of refractory or heat-insulating material `in connection with the pouring receptacle, thus conservng the heat of the slag.

Many changes may be made in the form of the receptacle, the steps in the process, etc., without departing from our invention.

We claim:

l. In the manufacture of wrought iron, the steps consisting of feeding molten ferrous material through a molten slag bath in a receptacle, and forming in the lower portion of the receptacle a ball having at least one horizontal dimension greater than its vertical dimension.

2. In the manufacture of wrought iron, the steps consisting of feeding granulated ferrous material through a molten slag bath in a receptacle, forming in its lower portion an elongated ball having one horizontal dimension greater than its vertical dimension, pouring off the surplus slag directly into another receptacle, again feeding granulated yferrous material therethrough to form another horizontally elongated ball, and removing the ball from the first receptacle and" colipressing it. the .steps which comprise feeding a stream of molten-ferrous material into a bath of molten We have found that by.

bath in a receptacle having one In the manufacture of wrought iron,

slag in a receptacle `andproducing a horithe bottom o the bath while maintaining a sufficient depth of slag over the metal to assure the granulation of the metal at the end of the pour, thereafter tilting the receptacle and pouring off the surplus slag, allowing the slag to drain from the ball, collecting the slag in another receptacle and feeding ferrous material through the bath of slag in the second receptacle while the slag is still molten.

4. In the manufacture of wrought iron, the steps consisting of feeding granulated ferrous material through a molten slag bath, conserving the heat of the bath by reducing heat losses therefrom, feeding the surplus slag while molten into another receptacle, and repeating the operation therein.

'5. In the manufacture of Wrought iron, the steps consisting of feeding granulated ferrous materal through a molten slag bath, retarding the loss of heat -through the walls of the receptacle, tilting the receptacle to feed the surplus slag while molten into another receptacle, retarding the heat losses through the second receptacle, removing the ball from the first receptacle and then compressing it, and pouring molten ferrous material into the slag in the second receptacle.

6. In the manufacture of wrought iron the steps consisting of feeding granulated ferrous material through a molten slag bath in a receptacle, retarding the heat losses through the walls of the receptacle, removing surplus slag while molten and feeding it into a second receptacle, retarding the heat losses through the Walls of the second receptacle, removing the ball. from the first receptacle and then compressing it, and feeding granulated ferrous material through the slag bath in the second receptacle while the same is still molten.

7. In the manufacture of wrought iron, the steps consisting of feeding hot granules of ferrous material through a molten slag transverse dimension greater than another, retarding heat losses through the walls of the receptacle, removing the surplus slag and the capsule from the receptacle, and feeding the slag into another receptacle, retarding heat losses through the walls of the second rel ceptacle and compressing the capsule removed from the first receptacle.

In testimony whereof we have hereunto set our hands.

JAMES ASTON. ADDISON H. BEALE.

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